Hydraulic salvage jack



Dec. 19, 1967 E. A. LINK 3,358,884

HYDRAULIC SALVAGE JACK Filed Oct. 4, 1965 5 Sheets-Sheet 1 INVENTOREDWIN A.LINK

' A'rroRNEY Dec. 19, 1967 E. A. LINK HYDRAULIC SALVAGE JACK 5Sheets-Sheet 2 Filed 001;. 4, 1965 FIG. 3b

FIG. 30.

INVENTOR. ED WIN A. L INK ATTORNEY Dec. 19, 1967 E. A. LINK 3,358,884

HYDRAULIC SALVAGE JACK Filed Oct. 4, 1965 5 Sheets-Sheet :5

INVENTOR. EDW/A/AL I/VK BY ATTORNEY Dec. 19, 1967 E, A, UNK 3,358,884

HYDRAULIC SALVAGE JACK Filed Oct. 4, 1965 5 Sheets-Sheet 4 INVENTOR. EDWIN/1. L INK ATTORNEY E. A. LINK Dec. 19, 1967 HYDRAULIC SALVAGE JACK 5Sheets-Sheet 5 Filed Oct. 4, 1965 INVENTOR. EDW/IVAL INK %M(AW vATTORNEY United States Patent 3,358,884 HYDRAULIC SALVAGE JACK Edwin A.Link, Binghampton, N.Y., assignor to Ocean Systems, Inc., a corporationof New York Filed Oct. 4, 1965, Ser. No. 492,715 1 Claim. (Cl. 22294)This invention relates to ships and to the field of marine salvage. Moreparticularly, it relates to novel apparatus for freeing a beached orgrounded ship, particularly a novel hydraulic jack.

Ships are frequently driven aground at high tide or in a storm; and, asa result of wave action, are frequently destroyed. If the ship is makingheadway when grounded, its momentum may carry it up on a reef and makeits re-fioating, even at high tide, impossible. There have been numerousprior-art attempts to provide means for increasing the buoyancy ofships. One general idea is to inflate bags with air after they areplaced under or alongside the hull. Abraham Lincoln received a patent ona bellows mechanism directed to this end.

Generally, it has been impractical to use such bags or pontoons in asurf, possibly because the wave action causes bouncing of the ship andworking of the fastenings with damage to both. Another difiiculty withgas bags comes from the instability of their lifting force. As a bagrises, its volum-n expands and its lift increases.

In common with these prior-art systems and apparatus, the presentinvention contemplates the use of expansible, flexible, bag-like,hydraulic cushions, connected together to provide a mattress to beplaced under the hull. In contrast with the prior art, the bags arefixed to the ground, not to the ship; and they are filled with water,not air.

The invention accordingly comprises the features of construction,combination of elements and arrangement of parts, all as exemplified inthe following detailed disclosure, and the scope of the invention willbe indicated in the claims.

It is an object of the present invention to provide means forstabilizing a grounded ship in a surf and for subsequently raising andfreeing it which may be handled and installed with a minimum of specialequipment. 'It is a further object to provide means for the above objectwhich may be employed under a wide variety of ground and hullconfigurations. A further object of the invention is to provideapparatus for ship salvage which is air-transportable in an emergency. Astill further object is to provide a novel expansible cushion adapted toserve as a hydraulic jack.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawings, in which:

FIG. 1 is an illustration of a grounded ship with lifting cushionsinstalled in accordance with the invention,

FIG. 2 is a plan view showing interconnections of the cushions andarrangement of ground tackle in FIG. '1,

FIG. 3 is a sketch of a hydraulic-jack cushion in expanded form,

FIGS. 30 and 3b are sections taken as shown in FIG. 3,

FIG. 4 shows the cushion of FIG. 3 in flattened condition,

FIG. 5 is a sketch showing a grease dispensing modification of the topof a cushion,

FIG. 6 is a sketch of an improvised form of lifting cushion for thepractice of the invention, and

FIG. 7 is a sketch of an alternative improvised lifting cushion.

FIG. 1 shows a ship 10 on a reef -12, the bow 14 is raised by pressurefrom the reef on the bottom 16. Under fiexure poses no problems.

the ship and extending between the bottom of the ship and the ground, orocean floor, are a plurality of accordian-like expansible hydrauliccushions 20-29. These cushions are fastened together and to cables -54,which with other cables, not shown, secure the assembly to the reef 12and the ocean floor 18. As will be more fully de veloped below, as thecushions 20-2-9 are pumped full of water and press against the bottom16, they apply a distributed pressure in excess of the normalhydrostatic pressure to an extended area of the ships bottom, therebyraising the ship and freeing it from contact with the reef. The ship isthen held only by friction between the bottom 16 and the tops of thecushions. This friction, unlike the engagement with the reef can bemanaged and controlled as set forth below.

If, as show-n, the bottom '16 of the ship is tilted, the pressure fromthe cushions (which is normal to the surface) has a horizontal componentin addition to a vertical component resisted by gravity. The ship willtend to move responsive to the horizontal component and the cushions totopple. To prevent this, ground tackle is arranged as shown in FIG. 2.

Assuming the ship is stuck forward on the centerline and port side, thecushions may be arranged amidships wherever the proximity of the bottomto the ground permits and cushions 28 and 29 may be extended forwardwhere clearance over the reef 12 permits.

As shown in the schematic plan view, FIG. 2, and in FIG. 3 the cells arepartially contained by inner cable hoops 69 and outer hoops 70 to whichconnecting rings 72 are fastened, four to each hoop. By hooking theserings 72 together with short lengths of chain, a mattresslike array ofthe cushions 20-3-9 is formed. Cables 51, 52 and 53 are stretched acrossthe cells and terminate in anchors 8188. The anchors are set before thecushions are expanded. In this way, the expansion of the cushions keepsthe cables tight and may even require that they be loosened somewhat.These cables prevent any toppling of the cushions to the side. Othercables 54, 5 5 and 56 strung fore and aft and anchored forward, preventthe cushions from being carried with the hull and tipped as the ship isreleased from the reef.

The cushions may be of various sizes and shapes. For a ship of about3,000 tons, displacement cushions as illustrated in FIGS. 3, 4 and 5 arepreferred. As an example, a U.S. Navy Allen M. Sumner class destroyer,displacing 3,300 tons fully loaded is 376 /2 feet long, 40% feet wideand draws 19 feet, maximum. Over most of its length the bottom issubstantially fiat to a width of 30 feet. Thus three such cushions each10 feet in diameter may be placed abeam. They may be extended to tenfeet more or less in height.

At the operating depth of 18 feet the bottom plates of the ship lyingquietly in the water distribute to the frames a pressure of about eightpounds per square inch. While Weight is kept to a minimum, and for thatreason, destroyers have been dubbed tin cans, nevertheless the hull mustbe designed to withstand several times this static pressure to stand upunder wave action, the shock of depth charges, etc. Thus one mayreasonably use 20 pounds per square inch as a design figure for theoverpressure to be exerted by the cushions, and, therefore also, thepressure which must be contained by the skin of the cushions.

For a cylinder ten feet in diameter under an internal pressure of twentypounds per square inch, the hoop stress is 1,200 pounds per lineal inch.Com-paring this with the 50,000 pounds per square inch strength of nylonfiber indicates that a two-ply bag of the order of onequarter inch thickwill sustain the pressure. This is so thin in comparison to the dimesions of the bag that It is preferred that cushions have a maximumexpansibility upward, while resisting outward expansion and shear. Theseobjectives are met with an aceordian-pleted bag 301 as shown in FIG. 3and sections 3a and 3b. The bag is molded in half-extended conditionover a similarlyshaped form bag. Reinforcing plies 311, 312 may beapplied over a liner 314 by cutting and cementing flat fabric pieces, bystretching knitted tubes, or by filament windmg.

Cable hoops in two sets 69, 70 are applied over the plies. Hoops 69 inthe first set are of lesser diameter and are placed one in each of thevalleys 320 of the accordion pleats. Hoops 70 from the second set areplaced one at each pleat crest 330, held in place by fabric strips 340.These hoops contribute importantly to maintaining the pressure againstlateral expansion without adding either stiffness, or resistance tovertical extension. The hoops also provide strong points to whichconnections may be made. For this purpose, interconnecting rings 72 arefastened to the outer hoops 70, by straps 352.

The accordion-pleated cylinder together with rounded end shoulders 360,361 is molded to its outer covering 365 and heat cured in the manner ofan automobile tire while still supported on its inflatable form bag.This form is then removed and each end piece 370 is applied. The ends370, which may be exposed to sharp and abrasive coral and toirregularities on the ship bottom which slide over the top, may bestiffer, multiplied and more thickly covered than the accordion-pleatedcylinder. Accordingly the ends inflate to a rounded, but nothemispherical condition, and readily conform to flat areas of thebottom.

It will be apparent that the cushions may be molded with any of a numberof rubber-like elastomers and rubbers, such as neoprene. Natural rubberwould probably not be used because of potential contact with fuel oil. Abronze ring 380 is fastened into the wall as shown in FIG. 3 andcontains a port 382 threaded with pipe threads, thereby providing apoint of connection through which fluids may be injected to expand thebag. Pressure may also be applied in this way to mold the ends to thepleated cylinder.

For placing the cushions under the ship, groups of cushions connectedtogether may be keel hauled by cables carried under the hull. Forplacement, the cushions are in their flattened condition, containing aminimum of liquid and no air. An excess of exterior pressure overinterior tends then to compress the bag to minimum length as shown inFIG. 4. Lines 401-403 between connecting rings 72 may be used tomaintain the cushion in compact condition for handling. A cushionextensible to 10 feet long may typically be so shortened to less than 2/2 feet in thickness.

When the ship is raised, there remains the job of pulling it over thetops of the cushions into deeper water. To provide a means forlubricating the tops of the cushions, the variation shown in FIG. 5 maybe used. The end closure 501 of the cushion comprises an attachment ring503 which is moulded to the bag shoulder 360. It is also moulded to themouth of a fluid-tight pouch 505, which extends into the cushion. Themouth of the pouch 505 is closed by a heavy netting 507 of nyloncordage, or such, which has many holes through it, but these holes aresufficiently small that the internal pressure of the cushion will besustained by the netting backed up by the material of the pouch 505. Thepouch 505 may be filled with heavy grease soap, or other lubricant whichis effectively retained by the netting until the internal pressureexceeds the external, pressing the pouch toward the netting, andextruding the grease.

To retain the grease until the ship begins to move over the cushions,the grease is preferably contained in a number of plastic bags, '509.Empty, these bags are passed through the netting into the pouch 505,leaving the necks 511 of these bags outside of the netting. To preparethe cushions for use, the plastic bags 509 are injected with grease, andtheir necks tied off and left protruding from the netting. When the shipstarts to move these necks 511 are pinched off, releasing the grease.

Alternatively a separate quilt or wafiie-like mat containing a number ofsmall lubricant pouches may be fastended to the cushion at the rings 72,and be arranged so that the pouches release the lubricant wherever thetop presses against the hull.

A cushion as just described is the preferred embodiment for a hydraulicjack to be used in this new method of salvage. It will be recognizedthat similar bag-like articles are already in use for other purposes.Fabric-reinforced elastomeric bags are now commonly used for theshipment of liquids by dry cargo methods. They are used for the storageof fluids on land and are particularly attractive for the storing ofpetroleum under water.

As shown in FIG. 6 similar hydraulic jacks may be improvised by pilingup a number of these bags 601 which are of a generally oblate spheroidalshape. These bags may be securely fastened together by webbing 603 whichmay, for convenience be cemented to the bag. These cushions 606, 607 maybe interconnected by linkage 608 to form mattresses as above described.

- Each of the bags 601 of such a cushion must be separately injected, byhoses 609 but otherwise the cushion is used substantially as thepreferred cushion may be used.

Also available in the trade are elongate fluid storage bags which may belaid up in the form of cribbing as shown in FIG. 7. The bags 701 are putdown in layers, criss-cross, and are held together with webbing 703 andinjected by hoses 704. In this way, the mattress under the ship may beinterlocked into a single structure, but injection of groups of bagsmust be under separate control as explained below.

As indicated above, pressures of up to about 20 p.s.i. (pounds persquare inch) may be exerted against a destroyer hull by cushions of thekind described operating as hydraulic jacks; and at most locations onthe hull such forces may be applied. Thirty of the pleated cushions asdescribed above, placed amidships could raise the destroyer used as anexample clear out of the water, but the hogging stresses might break herback. It follows, therefore that some attention must be given to theplace ment, of the cushions, and to the pressures which individualcushions or groups of cushions apply.

By adjusting the pressures in groups of cushions, the trim of the shipis controlled as it is eased off the reef. Ordinarily, the ship would bepulled free, while sliding along the length of the mattress. Pressure inselected cushions may be varied to steer the motion of the ship so thatit remains stably supported. Controlled fluctuation of the pressure ofgroups of cushions in cyclic order may be employed to control astep-by-step sliding of the ship over the mattress. The need for thesefunctions to have separate control of the pressure on individualcushions or groups of cushions sets a functional limit on the maximumdiameter of individual cushions. The required extended length ofcushions in turn largely determine the minimum practical diameter.

Ordinarily, the grounding force on a ship at high tide is only a smallfraction of her displacement. Three hundred-fifty tons for a 3,300 tondestroyer is typical. Thirty bags under such a ship can relieve it withonly about four p.s.i. pressure in the bags. A lighter construction ofthe bag may be contemplated in such a case.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained. Sincecertain changes may be made in the construction set forth withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawing shall be interpreted as illustrative and not in a limitingsense.

It is also to be understood that the following claim is intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

A hydraulic cushion comprising an expansible accordion-pleated bag ofelastomeric material; a pouch for containing a lubricant positionedWithin the upper portion of said cushion, said pouch having its outletcommunicating with the top surface of said cushion through a pluralityof small openings therein, whereby the lubricant will be retained insaid pouch until the internal pressure in said cushion is increased.

References Cited UNITED STATES PATENTS FOREIGN PATENTS 8/ 1939 GreatBritain.

ANDR'EW H. FARRELL, Primary Examiner. MILTON B UCHLER, Examiner.

